The tumor microenvironment state associates with response to HPV therapeutic vaccination in patients with respiratory papillomatosis.

Recurrent respiratory papillomatosis (RRP) is a rare, debilitating neoplastic disorder caused by chronic infection with human papillomavirus (HPV) type 6 or 11 and characterized by growth of papillomas in the upper aerodigestive tract. There is no approved medical therapy, and patients require repeated debulking procedures to maintain voice and airway function. PRGN-2012 is a gorilla adenovirus immune-therapeutic capable of enhancing HPV 6/11-specific T cell immunity. This first-in-human, phase 1 study (NCT04724980) of adjuvant PRGN-2012 treatment in adult patients with severe, aggressive RRP demonstrates the overall safety and clinically meaningful benefit observed with PRGN-2012, with a 50% complete response rate in patients treated at the highest dose. Responders demonstrate greater expansion of peripheral HPV-specific T cells compared with nonresponders. Additional correlative studies identify an association between reduced baseline papilloma HPV gene expression, greater interferon responses and expression of CXCL9 and CXCL10, and greater papilloma T cell infiltration in responders. Conversely, nonresponders were characterized by greater HPV and CXCL8 gene expression, increased neutrophilic cell infiltration, and reduced T cell papilloma infiltration. These results suggest that papilloma HPV gene expression may regulate interferon signaling and chemokine expression profiles within the tumor microenvironment that cooperate to govern clinical response to therapeutic HPV vaccination in patients with respiratory papillomatosis.

Adenosine A2A receptor activation reduces infarct size in the isolated, perfused mouse heart by inhibiting resident cardiac mast cell degranulation.

Mast cells are found in the heart and contribute to reperfusion injury following myocardial ischemia. Since the activation of A2A adenosine receptors (A2AARs) inhibits reperfusion injury, we hypothesized that ATL146e (a selective A2AAR agonist) might protect hearts in part by reducing cardiac mast cell degranulation. Hearts were isolated from five groups of congenic mice: A2AAR+/+ mice, A2AAR(-/-) mice, mast cell-deficient (Kit(W-sh/W-sh)) mice, and chimeric mice prepared by transplanting bone marrow from A2AAR(-/-) or A2AAR+/+ mice to radiation-ablated A2AAR+/+ mice. Six weeks after bone marrow transplantation, cardiac mast cells were repopulated with >90% donor cells. In isolated, perfused hearts subjected to ischemia-reperfusion injury, ATL146e or CGS-21680 (100 nmol/l) decreased infarct size (IS; percent area at risk) from 38 +/- 2% to 24 +/- 2% and 22 +/- 2% in ATL146e- and CGS-21680-treated hearts, respectively (P < 0.05) and significantly reduced mast cell degranulation, measured as tryptase release into reperfusion buffer. These changes were absent in A2AAR(-/-) hearts and in hearts from chimeric mice with A2AAR(-/-) bone marrow. Vehicle-treated Kit(W-sh/W-sh) mice had lower IS (11 +/- 3%) than WT mice, and ATL146e had no significant protective effect (16 +/- 3%). These data suggest that in ex vivo, buffer-perfused hearts, mast cell degranulation contributes to ischemia-reperfusion injury. In addition, our data suggest that A2AAR activation is cardioprotective in the isolated heart, at least in part by attenuating resident mast cell degranulation.

Effect of modulating cardiac A1 adenosine receptor expression on protection with ischemic preconditioning.

Activation of A(1) adenosine receptors (A(1)ARs) may be a crucial step in protection against myocardial ischemia-reperfusion (I/R) injury; however, the use of pharmacological A(1)AR antagonists to inhibit myocardial protection has yielded inconclusive results. In the current study, we have used mice with genetically modified A(1)AR expression to define the role of A(1)AR in intrinsic protection and ischemic preconditioning (IPC) against I/R injury. Normal wild-type (WT) mice, knockout mice with deleted (A(1)KO(-/-)) or single-copy (A(1)KO(+/-)) A(1)AR, and transgenic mice (A(1)TG) with increased cardiac A(1)AR expression underwent 45 min of left anterior descending coronary artery occlusion, followed by 60 min of reperfusion. Subsets of each group were preconditioned with short durations of ischemia (3 cycles of 5 min of occlusion and 5 min of reperfusion) before index ischemia. Infarct size (IF) in WT, A(1)KO(+/-), and A(1)KO(-/-) mice was (in % of risk region) 58 +/- 3, 60 +/- 4, and 61 +/- 2, respectively, and was less in A(1)TG mice (39 +/- 4, P < 0.05). A strong correlation was observed between A(1)AR expression level and response to IPC. IF was significantly reduced by IPC in WT mice (35 +/- 3, P < 0.05 vs. WT), A(1)KO(+/-) + IPC (48 +/- 4, P < 0.05 vs. A(1)KO(+/-)), and A(1)TG + IPC mice (24 +/- 2, P < 0.05 vs. A(1)TG). However, IPC did not decrease IF in A(1)KO(-/-) + IPC mice (63 +/- 2). In addition, A(1)KO(-/-) hearts subjected to global I/R injury demonstrated diminished recovery of developed pressure and diastolic function compared with WT controls. These findings demonstrate that A(1)ARs are critical for protection from myocardial I/R injury and that cardioprotection with IPC is relative to the level of A(1)AR gene expression.

Effects of A1 adenosine receptor stimulation on the expression of genes involved in calcium homeostasis.

We investigated whether A(1) adenosine receptor stimulation affects expression of genes involved in calcium homeostasis, including sarcolemmal L-type Ca(2+) channel, Na(+)/Ca(2+) exchanger, sarcoplasmic reticulum (SR) Ca(2+)-ATPase, phospholamban, or ryanodine receptor. Three models of A(1) stimulation were used: i) an acute model, i.e. isolated perfused rat hearts treated for 120 min with 15 nM R-phenylisopropyladenosine (R-PIA), an A(1) receptor agonist; ii) a subacute model, i.e. rats treated with 1.5 mg/kg R-PIA e.v. and sacrificed after 24 h; iii) a transgenic model, i.e. mice overexpressing A(1) adenosine receptors. In all models gene expression was determined by RT-PCR, and oxalate-supported Ca(2+) uptake, representing SR Ca(2+) uptake, was measured in the crude homogenate. Significant increase in the expression of the phospholamban gene was observed in each model of A(1) stimulation, while the expression of the other four genes was not significantly modified. In the acute model, SR Ca(2+) uptake was unaffected, however in the subacute and transgenic models uptake rate was significantly reduced. In parallel experiments, hearts obtained from the subacute model demonstrated a significant reduction in irreversible tissue injury from 30 min of ischemia and 120 min of reperfusion. Increased resistance to ischemia has already been reported also in our transgenic model. In conclusion, A(1) adenosine receptor stimulation up-regulates phospholamban gene expression, which leads within 24 h to a reduced rate of SR Ca(2+) uptake. Changes in Ca(2+) homeostasis might contribute to the delayed cardioprotective effect of adenosine.

Myocardial function following cold ischemic storage is improved by cardiac-specific overexpression of A1-adenosine receptors.

Cold ischemic storage of hearts for transplantation is limited to 4-6 h, and therefore the development of strategies to extend preservation time may increase the donor pool of hearts. Overexpression of A1-adenosine receptors (A1AR) can protect hearts from acute ischemic injury, and the purpose of this study was to test the hypothesis that overexpression of A1AR will improve tolerance to longer periods of cold ischemic preservation. Hearts from 18 wild type and 16 transgenic mice with overexpression of A1AR (A1AR Trans) were isolated and perfused, and then subjected to 18 h of preservation in 5 degrees C University of Wisconsin solution followed by 2 h of reperfusion. Left ventricular end diastolic pressure and left ventricular developed pressure were measured as indices of ventricular function. Cell viability was assessed by determination of infarct size and myocardial cell apoptosis. A1AR Trans hearts showed improved function following 18 h of ischemia, as shown by lower end diastolic pressure (p < 0.05) and higher recovery of left ventricular developed pressure (p < 0.05) during reperfusion. A1AR Trans hearts had markedly reduced infarct size (p < 0.05) and decreased apoptosis (p < 0.05). Overexpression of cardiac A1AR imparts cardioprotection during long-term cold ischemic preservation.

Altered sinus nodal and atrioventricular nodal function in freely moving mice overexpressing the A1 adenosine receptor.

To investigate whether altered function of adenosine receptors could contribute to sinus node or atrioventricular (AV) nodal dysfunction in conscious mammals, we studied transgenic (TG) mice with cardiac-specific overexpression of the A1 adenosine receptor (A1AR). A Holter ECG was recorded in seven freely moving littermate pairs of mice during normal activity, exercise (5 min of swimming), and 1 h after exercise. TG mice had lower maximal heart rates (HR) than wild-type (WT) mice (normal activity: 437 +/- 18 vs. 522 +/- 24 beats/min, P < 0.05; exercise: 650 +/- 13 vs. 765 +/- 28 beats/min, P < 0.05; 1 h after exercise: 588 +/- 18 vs. 720 +/- 12 beats/min, P < 0.05; all values are means +/- SE). Mean HR was lower during exercise (589 +/- 16 vs. 698 +/- 34 beats/min, P < 0.05) and after exercise (495 +/- 16 vs. 592 +/- 27 beats/min, P < 0.05). Minimal HR was not different between genotypes. HR variability (SD of RR intervals) was reduced by 30% (P < 0.05) in TG compared with WT mice. Pertussis toxin (n = 4 pairs, 150 microg/kg ip) reversed bradycardia after 48 h. TG mice showed first-degree AV nodal block (PQ interval: 42 +/- 2 vs. 37 +/- 2 ms, P < 0.05), which was diminished but not abolished by pertussis toxin. Isolated Langendorff-perfused TG hearts developed spontaneous atrial arrhythmias (3 of 6 TG mice vs. 0 of 9 WT mice, P < 0.05). In conclusion, A1AR regulate sinus nodal and AV nodal function in the mammalian heart in vivo. Enhanced expression of A1AR causes sinus nodal and AV nodal dysfunction and supraventricular arrhythmias.

Effects of A1 adenosine receptor overexpression on normoxic and post-ischemic gene expression.

OBJECTIVES: To identify potential molecular genetic determinants of cardiovascular ischemic tolerance in wild-type and transgenic hearts overexpressing A(1) adenosine receptors (A(1)ARs). METHODS: cDNA microarrays were used to explore expression of 1824 genes in wild-type hearts and ischemia-tolerant mouse hearts overexpressing A(1)ARs. RESULTS: Overexpression of A(1)ARs reduced post-ischemic contractile dysfunction, limited arrhythmogenesis, and reduced necrosis by approximately 80% in hearts subjected to 30 min global ischemia 60 min reperfusion. Cardioprotection was abrogated by acute A(1)AR antagonism, and only a small number (19) of genes were modified by A(1)AR overexpression in normoxic hearts. Ischemia-reperfusion significantly altered expression of 75 genes in wild-type hearts (14 induced, 61 down-regulated), including genes for metabolic enzymes, structural/motility proteins, cell signaling proteins, defense/growth proteins, and regulators of transcription and translation. A(1)AR overexpression reversed the majority of gene down-regulation whereas gene induction was generally unaltered. Additionally, genes involved in cell defence, signaling and gene expression were selectively modified by ischemia in transgenic hearts (33 induced, 10 down-regulated), possibly contributing to the protected phenotype. Real-time PCR verified changes in nine selected genes, revealing concordance with array data. Transcription of the A(1)AR gene was also modestly reduced post-ischemia, consistent with impaired functional sensitivity to A(1)AR stimulation CONCLUSIONS: Data are presented regarding the early post-ischemic gene profile of intact heart. Reduced A(1)AR transcription is observed which may contribute to poor outcome from ischemia. A(1)AR overexpression selectively modifies post-ischemic gene expression, potentially contributing to ischemic-tolerance.

A1 adenosine receptor overexpression attenuates ischemia-reperfusion-induced apoptosis and caspase 3 activity.

We tested the hypothesis that myocardial ischemia-reperfusion (I/R)-induced apoptosis is attenuated in transgenic mice overexpressing cardiac A(1) adenosine receptors. Isolated hearts from transgenic (TG, n = 19) and wild-type (WT, n = 22) mice underwent 30 min of ischemia and 2 h of reperfusion, with evaluation of apoptosis, caspase 3 activity, function, and necrosis. I/R-induced apoptosis was attenuated in TG hearts. TG hearts had less I/R-induced apoptotic nuclei (0.88 +/- 0.10% vs. 4.22 +/- 0.24% terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells in WT, P < 0.05), less DNA fragmentation (3.30 +/- 0.38-fold vs. 4.90 +/- 0.39-fold over control in WT, P < 0.05), and less I/R-induced caspase 3 activity (145 +/- 25% over nonischemic control vs. 234 +/- 31% in WT, P < 0.05). TG hearts also had improved recovery of function and less necrosis than WT hearts. In TG hearts pretreated with LY-294002 (3 microM) to evaluate the role of phosphosinositol-3-kinase in acute signaling, there was no change in the functional protection or apoptotic response to I/R. These data suggest that cardioprotection with transgenic overexpression of A(1) adenosine receptors involves attenuation of I/R-induced apoptosis that does not involve acute signaling through phosphoinositol-3-kinase.

Pertussis toxin sensitive and insensitive effects of adenosine and carbachol in murine atria overexpressing A(1)-adenosine receptors.

1 It was investigated how A(1)-adenosine receptor overexpression alters the effects of carbachol on force of contraction and beating rate in isolated murine atria. Moreover, the influence of pertussis toxin on the inotropic and chronotropic effects of adenosine and carbachol in A(1)-adenosine receptor overexpressing atria was studied. 2 Adenosine and carbachol alone exerted negative inotropic and chronotropic effects in electrically driven left atrium or spontaneously beating right atrium of wild-type mice. 3 These effects were abolished or reversed by pre-treatment of animals with pertussis toxin which can interfere with signal transduction through G-proteins. 4 Adenosine and carbachol exerted positive inotropic but negative chronotropic effects in atrium overexpressing A(1)-adenosine receptors from transgenic mice. 5 The positive inotropic effects of adenosine and carbachol were qualitatively unaltered whereas the negative chronotropic effects were abolished or reversed in atrium overexpressing A(1)-adenosine receptors after pre-treatment by pertussis toxin. 6 Qualitatively similar effects for adenosine and carbachol were noted in the presence of isoprenaline, beta-adrenoceptor agonist. 7 It is concluded that overexpression of A(1)-adenosine receptors also affects the signal transduction of other heptahelical, G-protein coupled receptors like the M-cholinoceptor in the heart. The chronotropic but not the inotropic effects of adenosine and carbachol in transgenic atrium were mediated via pertussis toxin sensitive G-proteins.

Gene expression profile of mouse myocardium with transgenic overexpression of A1 adenosine receptors.

Transgenic mice with cardiac-specific overexpression of adenosine A(1) receptors (A(1)AR) have demonstrated metabolic and functional tolerance to myocardial ischemia. We utilized cDNA microarrays to test the hypothesis that the cardioprotective mechanism(s) of A(1) overexpression involves altered gene expression. Total RNA extracted from the left ventricles from A(1) transgenic (n = 4) and wild-type (n = 6) mice was hybridized to Affymetrix mgU74A chips. Comparison of RNA expression levels in transgenic to wild-type myocardium revealed approximately 636 known genes with expression significantly altered by greater than 25%. We observed increased expressions of genes including NADH dehydrogenase, the GLUT4 glucose transporter, Na-K-ATPase, sarcolemmal K(ATP) channels, and Bcl-xl in A(1)AR-overexpressing hearts. We also observed decreased expression of pro-apoptotic genes including a 50% reduction in message level of caspase-8. Protein expression of GLUT4 and caspase-8 was also altered comparable to the differences in gene expression. These data illustrate genes with chronically altered patterns of expression in A(1) transgenic mouse myocardium that may be related to adenosine receptor overexpression-mediated cardioprotection.

A1 adenosine receptor overexpression decreases stunning from anoxia-reoxygenation: role of the mitochondrial K(ATP) channel.

Myocardial A1 adenosine receptor (A1AR) overexpression protects hearts from ischemia-reperfusion injury; however, the effects during anoxia are unknown. We evaluated responses to anoxia-reoxygenation in wild-type (WT) and transgenic (Trans) hearts with approximately 200-fold overexpression of A1ARs. Langendorff perfused hearts underwent 20 min anoxia followed by 30 min reoxygenation. In WT hearts peak diastolic contracture during anoxia was 45+/-3 mmHg, diastolic pressure remained elevated at 18+/-3 mmHg after reoxygenation, and developed pressure recovered to 52+/-4% of pre-anoxia. A1AR overexpression reduced hypoxic contracture to 29+/-4 mmHg, and improved recovery of diastolic pressure to 8+/-1 mmHg and developed pressure to 76+/-3% of pre-anoxia. Mitochondrial K(ATP) blockade with 100 microM 5-hydroxydecanoate (5-HD) increased hypoxic contracture to 73+/-6 mmHg in WT hearts, reduced post-hypoxic recoveries of both diastolic (40+/-5 mmHg) and developed pressures (33+/-3 %). In contrast, 5-HD had no effect on hypoxic contracture (24+/-8 mmHg), or post-hypoxic diastolic (10+/-2 mmHg) and developed pressures (74+/-3%) in Trans hearts. In summary, (i) A1AR overexpression improves myocardial tolerance to anoxia-reoxygenation, (ii) intrinsic mitochondrial K(ATP) channel activation decreases hypoxic contracture and improves functional recovery in wild-type hearts, and (iii) mitochondrial K(ATP) channels do not appear to play a major role in the functional protection from anoxia afforded by A1AR overexpression.